1.Biological characteristics of human amniotic fluid-derived embryonic mesenchymal stem cells isolated and cultured using the two-step method
Jianxun FENG ; Xiaolin LA ; Yan MA ; Xiaojuan BI ; Hao WEN
Chinese Journal of Tissue Engineering Research 2009;13(45):8854-8860
BACKGROUND:In vitro isolation and purity technique of stem cells mostly depends on the identification of cell surface marker,such as monoclonal antibody adherent spreading method,flow cell sorting method and immunomagnetic beads sorting method,but the operation was complicated and the price was high.OBJECTIVE:To observe the biological characteristics of human amniotic fluid-derived embryonic mesenchymal stem cells,which were isolated and cultured using the two-step method.DESIGN,TIME AND SETTING:The opening study was conducted at the Stem Cell Research Room of Xinjiang Medical University from March 2008 to March 2009.MATERIALS:Totally 10 amniotic fluid specimens were obtained from pregnant women who underwent prenatal diagnosis following 16-22 weeks of gestation or voluntarily induced abortion.With ultrasonic guidance,amniocentesis was performed to collect 20-40 mL amniotic fluid.METHODS:Human amniotic fluid-derived embryonic mesenchymal stem cells were isolated and cultured using the two-step method.Amniotic fluid was first centrifuged and incubated till spindle-shape cells were seen,with the presence of flbroblast-tike cell colonies.Supematant was moved to a new 25 cm~2 culture flask for further culture till spindle-shape fibroblast-like mesenchymal stem cell colonies.When 70% confluence,cells were digested,and incubated in α-MEM,supplemented with basic fibroblast growth factor,served as the first passage.MAIN OUTCOME MEASURES:Morphological changes in human amniotic fluid-derived embryonic mesenchymal stem cells of primary culture and subculture were measured.Karyotype,cycle,growth curve and colony formation ability of human amniotic fluid-derived embryonic mesenchymal stem cells were measured.Surface antigen and cytokine were examined using flow cytometry,immunofluorescence and RT-PCR.RESULTS:Human amniotic fluid-derived embryonic mesenchymal stem cells were successfully isolated and subcultured.During metaphase,primarily cultured amniotic fluid cells presented scattered spindle cells and flbroblast-like mesenchymal stem cell colonies every 7 days.Passaged cells completely adhered in 12 hours.Following 1 or 2 days of latent period,cells proliferated rapidly.About 90% confluence was observed following 6 or 7 days of culture.Cell arranged regularly,showing whirlpool-shape,radiated shape.Cells were spindle-shape,with unclear boundary.Chromosome karyotype of human amniotic fluid-derived embryonic mesenchymal stem cells was normal diploid.Growth curve showed "S" shape,but the two-step method reached a peak at (6.1±0.5) days,which was significantly rapid compared with the one-step method (7.2±0.6) days (P=0.035).Flow cytometry analyses showed that P3 cells at S phase took up (14±2.3)% using the two-step method,which was more than the one-step method (9.0±1.4)% (P=0.031).Low-density human amniotic fluid-derived embryonic mesenchymal stem cells were incubated for 7 days prior to cells formed scattered cell colonies.However,colony forming efficiency using the two-step method (15.0±2.3)% were significantly more than the one-step method (10.0±1.8)% (P=0.021).Flow cytometry results showed that human amniotic fluid-derived embryonic mesenchymal stem cells expressed CD44,CD29 and CD105,but were negatively for CD45,CD34,HLA-DR.Immunofluorescence suggested that Oct-4-positive cells were observed in amniotic fluid.However,the proportion of Oct-4-positive cells using two-step method (1.2±0.3)% was significantly greater than the one-step method (0.9±0.2)% (P=0.041).RT-PCR suggested that human amniotic fluid-derived embryonic mesenchymal stem cells obtained using the two methods expressed Oct-4.CONCLUSION:Human multipotent mesenchymal stem cells are present in human amniotic fluid.The two-step culture protocol could be a kind of high performance and simple protocol which may not interfere with the normal prenatal diagnosis procedure.
2.Effects of amniotic fluid stem cell transplantation on immune tolerance and oxidative stress in kidney transplantation Effects of amniotic fluid stem cell transplantation on immune tolerance and oxidative stress in kidney transplantation
Chunyang DENG ; Jianxun FENG ; Haiying ZHANG ; Tingfang CHEN ; Jing LI
Chinese Journal of Tissue Engineering Research 2015;(45):7342-7349
BACKGROUND:Stem cels can induce immune tolerance, prolong graft survival time and reduce rejection in organ transplantation, which have become a hot research. OBJECTIVE:To induce immune tolerance to alogenic kidney transplantation with amniotic fluid stem cels in recipient rats and to explore the mechanism underlying immune tolerance. METHODS: Amniotic fluid stem cels were isolated from Wistar rats. Two inbred male rat strains, Wistar rats and Sprague-Dawley rats, were selected as donors and recipients of kidney transplantation. The rat models of renal orthotopic transplantation were divided into the folowing four groups: a sham-operated group (n=10, Sprague-Dawley rats); an isograft group (n=10, Sprague-Dawley to Sprague-Dawley rats); a control group (n=10, Wistar to Sprague-Dawley rats, treated with 1 mL saline); and an experimental group (n=10, Wistar to Sprague-Dawley rats, treated with 1 mL of 3×106/L amniotic fluid stem cels). Serum levels of creatinine, urea nitrogen, interleukin-2, interferon-γ, parameters of oxidative stress were detected at 5 days after operation. Flow cytometry was employed to determine the percentage of CD4+ and CD8+ lymphocytes in the peripheral blood. Kidney transplants were observed pathologicaly. RESULTS AND CONCLUSION:Compared with the control group, the levels of creatinine, urea nitrogen, interleukin-2, interferon-γ, parameters of oxidative stress and proteinuria were lower in the experimental group (P < 0.05). Percentages of CD4+, CD8+ and CD4+/CD8+ ratio were also significantly lower in the experimental group than the control group. However, the rate of cretinemia clearance in the experimental group was significantly higher than that in the control group (P < 0.05). Furthermore, the degree of kidney injury in the experimental group was significantly lower than that in the control group. Our findings demonstrate that the amniotic fluid stem cel transplantation can induce immune tolerance, extenuate oxidative stress, attenuate pathological damage to the kidney transplant and preserve kidney function from acute rejection in rats undergoing kidney transplantation.
3.Study on correlation between psychological resilience, axiety, depression, coping styles and social supports among parents of preterm infants of ophthalmic clinic
Chunyan LIANG ; Wanhua XIE ; Daoman XIANG ; Feng CHEN ; Jianxun WANG
Chinese Journal of Practical Nursing 2017;33(14):1054-1059
Objective To explore psychological resilience, anxiety, depression, coping styles and social supports status among parents of preterm infants of ophthalmic clinic, and analyze their relationship. Methods A total of 217 parents of preterm infants at ophthalmic clinic of hospital were selected by convenience sampling method and investigated by self- designed general information questionnaire, Connor-Davidson Resilience Scale, Self-rating Anxiety Scale, Self-rating Depression Scale, Social Support Rating Scale, and Simplified Coping Style Questionnaire. Results The total score of psychological resilience was (67.48 ± 14.20) points. The average score of positive coping styles dimension was (1.98±0.50) points, and negative coping style dimension score was (1.19±0.55) points. The social support score was moderate with a total score of (42.75 ± 6.17) points, the anxiety and depression got a total score of (36.77 ± 8.17) points and (39.67 ± 9.02) points respectively. Psychological resilience was negatively correlated with anxiety and depression (r=-0.363--0.242, P<0.01), and was positively correlated with coping styles and the social support (r=0.141-0.312, P<0.05 or 0.01). Multi-factor linear regression analysis showed that depression and social support were the influence factors of psychological resilience(t=-4.376, 2.516, P<0.01 or 0.05). Conclusions The parents of preterm infants are at the poor psychological states. Coping styles and depression are the important factors which affect psychological resilience among parents of preterm infants. Nurses should assess the psychological status of the parents, provide targeted interventions to relieve stress, guide the parents use social support effectively, and improve their psychological state.
4.Construction of Raji-Luc CD19 KO Lymphoma Cell Line Using CRISPR/Cas9 Technology
Jingjing LIU ; Xiuying LIU ; Yaru FENG ; Yichao FENG ; Mengyuan YU ; Jianxun WANG
Journal of Modern Laboratory Medicine 2024;39(1):10-15,99
Objective To construct Raji-Luc lymphoma cells with CD19 knockout using CRISPR/Cas9 technology and preliminarily validate their immune escape ability.Methods PB-CRISPR-CD19 small guide RNA(sgRNA)plasmids was constructed,the optimal sgRNA sequence was screened,and Raji-Luc cells with pCAG-PBase,PB-CD19 sgRNA,and PB-CRISPR-Cas9 were co-transfected.Stable knockout monoclonal cell lines were screened by flow sorting and limit dilution method and the knockout effect was verified through gene sequence testing.The expression of luciferase on the surface of the cell line was detected by microplate reader,CD19 CAR-T and CD38 CAR-T previously constructed in the laboratory were used as effector cells,and the immune escape ability of Raji-Luc CD19 KO cell line was verified by universal luciferase chemiluminescence method.Results The transfection efficiency of Raji-Luc CD19 KO cells prepared by electro transfection was high,and the knockout efficiency of the two monoclonal cells was more than 99%.There was no significant difference in luciferase expression compared to the original Raji-Luc cells,and CD19 CAR-T cells could not be activated to the kill them.Conclusion Successfully constructed Raji-Luc CD19 KO lymphoma cell line.
5.Expression and crystallographic studies of a fungal immunomodulatory protein LZ-8 from a medicinal fungus Ganoderma lucidum.
Min AN ; George Fu GAO ; Jianxun QI ; Feng LI ; Xingzhong LIU
Chinese Journal of Biotechnology 2010;26(11):1563-1568
LZ-8 protein, isolated from a well known Chinese traditional medicinal fungus Ganoderma lucidum, is the first member of fungal immunomodulatory protein, members of which have been isolated from a variety of medicinal and edible mushrooms in the last two decades. The protein plays a multifunctional and important role in modulating immune system. In this report, in order to get LZ-8 protein crystals, the LZ-8 gene was expressed and purified by affinity chromatography, gel filtration chromatography and anion exchange chromatography subsequently. The protein was then crystallized using the hanging-drop vapour-diffusion method. The LZ-8 crystals were obtained and the phase information was calculated by X-ray diffraction. The resolution of LZ-8 crystals is 3.2A. This study will provide an insight into the structure of fungal immunomodulatory proteins.
Animals
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Crystallography
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Fungal Proteins
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biosynthesis
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genetics
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immunology
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Ganoderma
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genetics
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metabolism
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Genetic Vectors
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genetics
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Immunologic Factors
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biosynthesis
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genetics
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Mice
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Recombinant Proteins
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biosynthesis
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genetics
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immunology
6.Genetic instability in cancer tissues analyzed by random amplified polymorphic DNA PCR.
Jianxun WANG ; Qianwen WANG ; Feng YE
Chinese Medical Journal 2002;115(3):430-432
OBJECTIVETo detect DNA and chromosomes instabilities during the progression of tumors and screen new molecular markers coupled to putative or unknown oncogenes and/or tumor suppressor genes.
METHODSFive kinds of tumors, in a total of 128 specimens, were analyzed by random amplified polymorphic DNA (RAPD) PCR. Bands representing instabilities were recovered, purified, and cloned, labeled as probes for Southern and Northern blot analysis and DNA sequencing.
RESULTSSample 5 and 3 of the gastric cancer tissues showed the highest genomic changes and the average detectability in five cancers was up to at least 40% (42.2% - 49.4%). There were significant differences in the ability of each primer to detect genomic instability, which ranged from 27% (primer 8) to 68% (primer 2). Band B is a single copy fragment, and was found to be an allelic loss in gastric and colon cancers. It is a novel sequence and was registered in GenBank with Accession Number AF151005. Further analysis revealed that it might be part of a cis-regulatory element of a new tumor suppressor gene, containing a promoter of cis-action "CACA" box, an enhancer of "GATA" family and a start codon.
CONCLUSIONSIt was impossible or difficult to get great achievements for cancer treatments with the procedure of gene therapy only to one oncogene or one tumor suppressor gene because the extensive DNA variations occurred during the progression of tumor. RAPD assay connected with other techniques was a good tool for the detection of genomic instabilities and direct screening of some new molecular markers related to tumor suppressor genes or oncogenes.
Base Sequence ; Blotting, Southern ; Colonic Neoplasms ; genetics ; pathology ; Humans ; Liver Neoplasms ; genetics ; pathology ; Lung Neoplasms ; genetics ; pathology ; Molecular Sequence Data ; Neoplasms ; genetics ; pathology ; Polymorphism, Restriction Fragment Length ; Random Amplified Polymorphic DNA Technique ; Sequence Analysis, DNA ; Stomach Neoplasms ; genetics ; pathology
7.A dimeric structure of PD-L1: functional units or evolutionary relics?
Yong CHEN ; Peipei LIU ; Feng GAO ; Hao CHENG ; Jianxun QI ; George F GAO
Protein & Cell 2010;1(2):153-160
PD-L1 is a member of the B7 protein family, most of whose members so far were identified as dimers in a solution and crystalline state, either complexed or uncomplexed with their ligand(s). The binding of PD-L1 with its receptor PD-1 (CD279) delivers an inhibitory signal regulating the T cell function. Simultaneously with the Garboczi group, we successfully solved another structure of human PD-L1 (hPD-L1). Our protein crystallized in the space group of C222(1) with two hPD-L1 molecules per asymmetric unit. After comparison of reported B7 structures, we have found some intrinsic factors involved in the interaction of these two molecules. Based on these results, we tend to believe this uncomplexed hPD-L1 structure demonstrated its potential dimeric state in solution, although it could just be an evolutionary relic, too weak to be detected under present technology, or still a functional unit deserved our attentions.
Antigens, CD
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chemistry
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immunology
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B7-H1 Antigen
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Crystallography, X-Ray
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Evolution, Molecular
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Humans
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Protein Multimerization
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Protein Structure, Quaternary
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Protein Structure, Secondary
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T-Lymphocytes
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chemistry
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immunology
8.Effect of Xuebijing Injection on differentiation of bone marrow hematopoietic stem cells in septic mice
Jun WANG ; Ping WANG ; Ying HAO ; Xiaorui LI ; Yaru FENG ; Lan WANG ; Hongcai SHANG ; Jianxun WANG
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2019;26(5):539-542
Objective To investigate the intervention effect of Xuebijing Injection on the differentiation of bone marrow hematopoietic stem cells (HSC) in septic mice. Methods Fifty-four male C57BL/6N mice were randomly divided into three groups: normal control group, model group and Xuebijing group, each group with 18 mice. The mouse models of sepsis were duplicated by intra-peritoneal injection of 10 mg/kg E. coli lipopolysaccharide (LPS) method. Starting from the day of modeling, Xuebijing Injection 20 mL/kg was intravenously injected into the tail vein in Xuebijing group, once a day for consecutive 4 days; the normal control and model groups were intravenously injected with normal saline at the same dose and site for 4 days. The bone marrow cells of the femur and tibia of the mice were isolated after 4 days of various treatments in the three groups, and the proportions of bone marrow HSC Lin-Sca-1+c-Kit+ (LSK) and hematopoietic progenitor cells Lin-Sca-1-c-Kit+ (LS-K) of each group were detected by flow cytometry. Results Finally, 14 mice were included in the normal control group, 17 in the model group, and 12 in the Xuebijing group. With the prolongation of time, the body weight of the normal control group gradually increased, the body masses of the model group and the Xuebijing group were decreased first and then increased, reaching a peak at 96 hours after the model was established, but they were still significantly lower than the body mass of normal control group (g: 19.81±0.27, 19.58±0.39 vs. 22.23±0.30, both P < 0.05). Compared with the normal control group, the proportions of LSK, LS-K, long-term HSC (LT-HSC), and megakaryocyte-erythroid progenitor cells (MEP) were all significantly increased in the model group [LSK: (16.62±1.28)% vs. (12.89±0.83)%, LS-K: (44.77±1.77)% vs. (30.34±0.90)%, LT-HSC: (6.88±0.48)% vs. (1.83±0.24)%, MEP: (13.89±1.26)% vs. (9.38±0.66)%, all P < 0.05], the proportion of multipotential progenitor cells (MPP) was significantly decreased [(2.41±0.34)% vs. (5.99±0.59)%, P < 0.05]. Compared with the model group, the LSK and myeloid progenitor (CMP) of the Xuebijing group were significantly reduced [LSK: (12.25±0.69)% vs. (16.62±1.28)%, CMP :(0.31±0.05)% vs. (0.55±0.13)%, both P < 0.05], and LS-K, LT-HSC, MEP showed a decreasing trend [LS-K: (42.75±2.48)% vs. (44.77±1.77)%, LT-HSC:(5.98±0.70)% vs. (6.88±0.48)%, MEP: (10.94±1.36)% vs. (13.89±1.26) %], but the differences were not statistically significant (all P > 0.05). There were no significant differences in the proportions of short-term HSC (ST-HSC) and granulocyte-macrophage progenitor cells (GMP) among the three septic groups (all P > 0.05). Conclusion Xuebijing Injection can improve the differentiation function of bone marrow cells in septic mice, which may be possibly related to the inhibition of pathological proliferation of bone marrow hematopoietic stem cells and progenitor cells in septic mice by Xuebijing Injection.
9.Crystal structure of the swine-origin A (H1N1)-2009 influenza A virus hemagglutinin (HA) reveals similar antigenicity to that of the 1918 pandemic virus.
Wei ZHANG ; Jianxun QI ; Yi SHI ; Qing LI ; Feng GAO ; Yeping SUN ; Xishan LU ; Qiong LU ; Christopher J VAVRICKA ; Di LIU ; Jinghua YAN ; George F GAO
Protein & Cell 2010;1(5):459-467
Influenza virus is the causative agent of the seasonal and occasional pandemic flu. The current H1N1 influenza pandemic, announced by the WHO in June 2009, is highly contagious and responsible for global economic losses and fatalities. Although the H1N1 gene segments have three origins in terms of host species, the virus has been named swine-origin influenza virus (S-OIV) due to a predominant swine origin. 2009 S-OIV has been shown to highly resemble the 1918 pandemic virus in many aspects. Hemagglutinin is responsible for the host range and receptor binding of the virus and is therefore a primary indicator for the potential of infection. Primary sequence analysis of the 2009 S-OIV hemagglutinin (HA) reveals its closest relationship to that of the 1918 pandemic influenza virus, however, analysis at the structural level is necessary to critically assess the functional significance. In this report, we report the crystal structure of soluble hemagglutinin H1 (09H1) at 2.9 Å, illustrating that the 09H1 is very similar to the 1918 pandemic HA (18H1) in overall structure and the structural modules, including the five defined antiboby (Ab)-binding epitopes. Our results provide an explanation as to why sera from the survivors of the 1918 pandemics can neutralize the 2009 S-OIV, and people born around the 1918 are resistant to the current pandemic, yet younger generations are more susceptible to the 2009 pandemic.
Animals
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Cloning, Molecular
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Crystallography, X-Ray
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Hemagglutinin Glycoproteins, Influenza Virus
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chemistry
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genetics
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immunology
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isolation & purification
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Influenza A Virus, H1N1 Subtype
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chemistry
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genetics
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immunology
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Models, Molecular
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Protein Conformation
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Swine
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virology